The major objectives of the Center are to advance our understanding of learning disabilities through a multidisciplinary and integrative effort. The central theme of the research program is tackling complexities of learning disabilities in context. We do so by applying state-of-the-art methods that make realistic models of learning disabilities tractable. Our approach is multi-disciplinary, with representation from fields of molecular genetics, behavior genetics, teacher education, educational psychology, developmental psychology, cognitive psychology, and cognitive science. The Center comprises six projects and four cores. Project I, Definition, Classification, and Subtyping develops and tests a new multivariate model of learning disabilities. Project II, Learning Disabilities, Reading Comprehension, and the Classroom Environment, examines the learning context of students with reading disabilities. Project III, A Longitudinal and Experimental Investigation of Written Expression, examines the development of writing and disabilities in written expression in context. Project IV, the Florida Twin Project on Reading, Behavior, and Environment, analyzes the interplay of genes and environments in a large-scale twin study. Project V, Development of Executive Functioning, Attention, and Reading Skills/Disability In Young Children, examines the development of executive functioning from preschool on. Project VI, Genomic Sequence Pattern Analyses in African-American Families with Severe SRD, analyzes genomic bases of reading disability. The work of the Centers is supported by four cores: an Administrative Core, a Service Core, a Data Core, and a PMRN Core.